A Special Trees Aside.
MSFS has the correct tree location and species data, but it assumes any tree is fully grown and at max height, when life is unfortunately not that kind to our arboreal friends. The result is the trees look too big. They look good from > 5000 ft, but too bushy and lush below that.
This is a general hack you can do to edit them, although this might interfere with updates when they come. If you edit a file, back it up first.
Go here:
X:\MSFS\Official\OneStore\fs-base\vegetation
(Where X:\MSFS is where your Content Manager location is, it may be your install location) (*)
and edit this guy:
10-asobo_species.xml
In that file you’ll find the various tree species, all laid out. The values to adjust are the
<Size min="15" max="20"/>
..values. You can usually take off 5 from each value, but it’s completely up to taste of how treey you like the world in your location.
(*) Dammit, now I need another aside on default install location. 
. Because the client app will need to be on the Xbox platform, it’s written as a Univeral Windows Platform (UWP) device compatible application. This means it’s sort of ‘sandboxed’ for security and uniform API usage. It also means that via the Windows Store, it puts it somewhere odd like:
X:\Users\(you)\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\Packages
..where X is your default Apps drive and (you) is your windows username. The ‘library’ part of MSFS is called the ‘Content Manager’ and other than making Steam purchases mad that they can’t refund because it took 3 hours to download, its purpose is to be a ‘versioning system lirbary’ for first and third party content. The default install will put your ‘Content Manager’ content in a location a bit like the one above, so hunt around. I personally like it on a separate directory to be easier to find. You can always tell the ‘root’ of it, as it has ‘Community’ and ‘Official’ split directories for future library stuff.
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